OK, while waiting for the circuit board to be ready, I have also ordered the SSOP to DIL adapter. In the meantime, its time to fine-tune the electronics. I have done this design late least year but because there were no physical model for me to design the PCB, it was kept on hold. I have, by this time, decided on the battery pack to be 4.5 volts since a White LED needs at least 3 volts to run.

So, with the Youtube videos of the actual prop as source, I got the timing as close as possible.But not too close since in this scale, the light from one LED to another would be 'jumping' instead of 'sweeping'.